It needs a tensioning device to clamp a central hole of a hub in an automobile hub machining process, and due to higher requirement of the machining precision of the hub, it is necessary to require that the tensioning device has excellent precision.
In one aspect, it needs that the tensioning device can provide a stable tensioning force in a hub machining process. If the tensioning force is smaller than a certain numerical value, the hub cannot be well clamped and is possible to loosen in the machining process, thereby seriously influencing the machining quality of the hub; and if the tensioning force is larger than a certain numerical value, the hub will generate elastic deformation, even plastic deformation, thereby directly influencing the size precision of the hub. Furthermore, if the tensioning force is larger in the machining process, and when the tensioning device is loosened after the hub is machined, the hub generates a stress release situation, so that the machining precision of the hub is influenced again.
In the other aspect, the tensioning device generally is provided with multiple contacts, and the contacts need to have excellent synchronicity to ensure the machining precision of the hub. If the contacts cannot synchronously act on an inner hole of the hub, the hub may be inclined, and then the final machining size of the hub is extremely poor.
In view of the requirements in the above two aspects, there is an urgent need of developing a high-precision tensioning device to meet higher requirement of the machining precision of the hub.